Install Fog (Aux) Lamps

[tannerr52]

Hello all, I am back.
SO here is my dilemma. I want to install driving lights (aux lights) on my car as my lights aren't all that bright. (and They're cool! anyway, I was wondering a few things.
1. Should I wire up a separate switch (really no spot for it) or could I just hook them up to the park light switch?
2. How would i go about the lights turning off automatically when my brights are on? Or should i go about this in a different way? (at least that's how it is on factory cars)

I'm thinking just a 20-30 dollar light kit from my local parts store. (will there be any instructions included?

Thanks, Tanner

[shorod]

Most driving/fog light kits from the factory also do not come on with the parking lights, but rather only with the low beam headlights. This is logical for fog lights since, if you need fog lights, you do not want to be using the high beam headlights. Anyway, if you want to retain this feature, my suggestion would be to use a relay (it would be a good idea to use a relay anyway) and have a fused source from the battery to terminal 30 of the relay. Then run a wire from terminal 87 to the power lead for the fog lights. The ground for each of the fog lights should be tied to a good ground location near the fog lights.

If you're using a lighted switch for the fog lights, you'll want to understand how the switch works (does it switch the power lead or the ground lead?). If it switches the power lead (most likely) you'll want to connect terminal 86 of the relay to ground. Then run a wire from the headlight switch that is hot when the low beam headlights are active to the "12V" terminal of the lighted switch. Connect the switch output to terminal 85 of the relay. Connect the switch ground terminal to a good ground near the switch location.

If you decide to just have the driving lights come on with the low beam headlights, then you could connect the wire from the low beam headlights directly to terminal 85 of the relay.

-Rod

[tannerr52]

Ok, i did some digging around and found this picture. Does this seem about right? Where it says " Hi Low Ign" where will that wire go? Do i tap directly into the wire that leads to *blank*... I have another picture i found but it over complicates it i believe...

[jdmccright]

Yes that looks correct. Just be sure that the low beams do in fact turn off when the high beams are on. Otherwise, they will remain on.

[shorod]

Originally Posted by tannerr52

Where it says " Hi Low Ign" where will that wire go?

If you want the fog lights to only be able to work with the low beam headlights, this wire would connect to a feed that is only battery voltage with the low beams on. Since the switch will likely be installed in the cabin of the vehicle, you would want to pull this feed from the headlight switch. The fuse feeding the switch is a good idea, that way if you short your wiring for the fog light switch it will not blow the fuse for your headlights.

The switch this diagram uses is a non-lighted switch. If you plan to install a switch that lights up when the fog lights are on you'll need to add a ground to switch AND confirm that the switched lead is the hot lead rather than ground.

If you tell us the year, make and model of the car you'll be installing these in to, we can probably tell you the wire color at the headlight switch that you'll want to connect to.

-Rod

[tannerr52]

Originally Posted by shorod

If you tell us the year, make and model of the car you'll be installing these in to, we can probably tell you the wire color at the headlight switch that you'll want to connect to.

Its going into a 90 Bonneville. I think i might have an idea of where its located, but where will this relay be? I'm also pretty sure where the headlight switch is too, but not 100 percent.
Sorry, I havent really done much electrical with cars....

[MagicRat]

Originally Posted by jdmccright

Just be sure that the low beams do in fact turn off when the high beams are on. Otherwise, they will remain on.

This certainly was the case with my Bonneville, (same vintage as the thread starters one).

I found this annoying because, as noted, these lights are barely adequate. I only got decent illumination on dark roads by holding the turn signal lever back all the way which activates both high and low beam.

A logical mod would be to install a relay to energise the low beam circuit whenever the high beams are on.

[shorod]

Looks like the low beam wire you're looking for is the tan wire from the headlight switch. As for he location of the headlight switch, I'm not familiar enough with the Bonneville to know where that is, but it's likely just behind the knob that you turn or pull to turn the headlights on with.

-Rod

[tannerr52]

Ok! one last question. will i just use a qucksplice on this wire? and another question (:P) not as important....where will i wire up to illuminate the switch? i think thats my last 2 questions. Thanks

[shorod]

You could tap in to the low beam headlight wire with a quick splice as long as you're making the splice inside the cabin of the vehicle. If you are splicing in to a wire under the hood or where the splice could be exposed to the elements, don't use a quick splice. My preference, regardless of location though, would be solder and adhesive-lined shrink sleeving.

Assuming you use an illuminated switch, and assuming the illuminated switch switches the feed line to the load line, you'd connect the low beam wire to the Feed/+12V terminal of the switch, you'd connect the fog light relay lead to the load/[light symbol] terminal of the switch, then you'd need to connect a ground wire to the GND/- terminal of the switch. This way when you the low beam headlights are on, there is battery power to the feed terminal of the switch, when the switch is turned "On" power from the feed terminal lights the switch illumination and also passes on to the relay.

-Rod

[tannerr52]

Ok, just because im curious... Is there a way that i could use the park light switch as the switch in the diagram? thought it would make it cleaner.

[tannerr52]

Everything is going great so far! Still got to mount the lights. (not drill bit grr) found a nice place to mount them. Still have to run switch wore through firewall, clean up a bit, and were golden!

[shorod]

Originally Posted by tannerr52

Ok, just because im curious... Is there a way that i could use the park light switch as the switch in the diagram? thought it would make it cleaner.

Sorry, missed this question. Yes, if you want the fog lights to come on every time the parking lights (or headlights) are turned on, you could just connect a wire from the parking light circuit to terminal 86 as shown in the diagram. In this way, you wouldn't need to run a wire in to the cabin, you could just tap in to the parking light circuit under the hood. However, the fog lights would NOT turn off with the high beams if wired this way.

If you were to connect a wire from the low beam filament of the headlights to terminal 86, that would turn the fog lights on with the low beam headlights and off with the high beams, but would not turn the driving lights on with the parking lights (only the headlights).

-Rod